Stolze, Joachim2008-06-032008-06-031985Stolze, Joachim: On the validity of certain variational principles for the free energy. In: Progress of Theoretical Physics Nr. 1, Jg. 73(1985), S. 281-283, doi: 10.1143/PTP.73.281.10.1143/PTP.73.281http://hdl.handle.net/2003/2541810.17877/DE290R-3395enProgress of Theoretical Physics510On the Validity of Certain Variational Principles for the Free Energyarticle (journal)